This is beta-amyloid peptide amino acids 1 to 42 where Gly37 is replaced by the negatively charged Asp. This substitution completely abolishes neurotoxic and oxidative processes associated with the parent peptide, resulting in the lack of cell toxicity and protein oxidation in contrast to those observed in the native beta-amyloid 1 to 42. G37D peptide does not display the aggregation properties that are associated with native beta-amyloid.